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Multi-Purpose EPS Underlayment

FanFold - Multi-Purpose EPS Underlayment
Overview Header
FanFold by Plasti-Fab® is designed to provide a continuous insulating
underlayment that will help to reduce air leakage that can create drafts that
carry dust and dirt into the building envelope.

FanFold by Plasti-Fab® consists of an expanded polystyrene (EPS)
insulation core material with a thin film laminated to both sides. The
branded film includes horizontal & vertical gridlines spaced at 51 mm (2’’)
on centre to assist with installation. FanFold is manufactured by Plasti-Fab®
so that each piece folds into a stack that can be handled easily. On the
jobsite Fanfold opens into a 1.22 m x 3.66 m (4 ft x 24 ft) section that
covers a large area quickly.

All of these features add up to make FanFold one of the most versatile
products on the market today.

Available in 1.22 m x 3.66 m (4 ft x 24 ft)
Thickness: 1/2 inch, 3/8 inch
Bundle includes: 2 pcs , 192 sq ft total coverage

Features and benefits:
• Superior lay-flat design provides smooth surface for installation of new
siding over old
• Quick and easy application for labor saving efficiency
• Lightweight, easy handling and installation

Roofing or Reroofing
Plasti-Fab FanFold has multiple uses on new roofs such as protecting
expanded polystyrene insulations from direct contact with membranes,
added membrane protection for high traffic roofs or as an added shield to
protect membranes from damage due to hail and the harmful effects of
the sun. FanFold cushions the membrane with its EPS core and protects
membranes with its laminated/branded thin film on both sides.Simply apply
FanFold above or below the roof membrane using approved fastening
methods, then finish as specified. FanFold is easy to use in a roof recovery
system which saves considerable time and labour costs. FanFold includes
an EPS core which cushions the membrane while the laminated/branded
thin film on both sides provides a smooth finish for application of the

Protection Board
Damaged dampproofing or waterproofing membrane is often the cause
of foundation leakage which can be expensive to repair. FanFold can
be applied over the top of the membrane to protect it from damage
during backfill placement. Plasti-Fab FanFold underlayment provides a
drainage plane directing moisture toward the drain tile before it reaches
the foundation wall further reducing the chance of water infiltration into
the basement.FanFold underlay can easily be installed over either
sprayed-on or peel and stick membranes. To install, just attach FanFold
using any adhesive compatible with foam plastic insulation and start

Re-siding Application
The most common way of enhancing a home’s beauty & resale value is by
re-siding. FanFold by Plasti-Fab® provides a continuous insulating
underlayment for new siding. Place FanFold directly over the existing
exterior finish and attach using fasteners that will penetrate through the
existing siding to a nailable substrate. The grid lines assure that the siding
is placed level as well as providing straight lines for cutting around door
and window openings.

New Construction
Use FanFold as an insulating underlayment beneath new siding on exterior
walls. Install FanFold underlay as a sheathing material attached directly
to the studs or over wood sheathing using nails. All types of exterior
finishes can be used and are attached through FanFold underlay and into
the studs. FanFold by Plasti-Fab® used beneath siding provides a continuous
insulating underlayment that reduces air infiltration, reducing heating and
cooling costs.
Applications using FanFold

Fanfold Applications

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Specification Header

The table below provides material properties for PlastiSpan insulation meeting CAN/ULC-S701, Type 1.

Material Property Test Method Units Property Values
Thermal Resistance
Minimum RSI per 25mm (R per inch)
Compressive Resistance
Minimum @ 10% Deformation
Flexural Strength
Water Vapour Permeance2
Water Absorption3
% By volume 6.0
Dimensional Stability
Maximum, 7 Days @ 70± 2℃ (158±40F)

% Linear Change 1.5
Limiting Oxygen Index
% 24
Thermal Resistance for Some Common Thicknesses
Millimeters RSI Inches R-value
19 0.49 3/4" 2.81
25 0.65 1" 3.75
38 0.98 1 1/2" 5.63
50 1.30 2" 7.50
75 1.95 3" 11.25
Other Standard & Custom thicknesses available upon request.
Standard sizes range from; 2x4,2x8,4x4,4x8. Customer sizes upon request.